肝門部胆管狭窄の病理―良・悪性疾患―

Pathology of Hilar Biliary Stricture: Benign and Malignant Lesions

要　旨

肝門部胆管が狭窄するには，肝門部胆管自体の病変によるものの他，肝門部胆管外の病変でも起こりうる。狭窄する病因は，さまざまである。非腫瘍性病変としては，胆管炎，胆道結石症，原発性硬化性胆管炎，IgG4関連硬化性胆管炎，免疫チェックポイント阻害薬によるirAE硬化性胆管炎，術後性胆管炎，虚血性胆管炎，アミロイドーシスなどがあげられる。腫瘍もしくは腫瘍様病変では，胆管上皮内腫瘍（BilIN），胆管内乳頭状腫瘍（IPNB），胆道癌，神経内分泌腫瘍，胆管周囲囊胞，転移などの他，胆管外病変である肝細胞癌や断端神経腫などでも狭窄の病因となりうる。

　The perihilar bile duct can be narrowed by lesions in the perihilar bile duct itself or by lesions outside the perihilar bile duct. The etiologies for stenosis are varied. Non-neoplastic lesions include cholangitis, biliary stone disease, primary sclerosing cholangitis, IgG4-related sclerosing cholangitis, irAE sclerosing cholangitis, postoperative cholangitis, ischemic cholangitis and amyloidosis. Neoplasia or tumor-like lesions such as biliary intraepithelial neoplasia (BilIN), intraductal papillary neoplasm of the bile duct (IPNB), biliary tract carcinoma, neuroendocrine neoplasm, peribiliary cyst, metastases, as well as hepatocellular carcinoma and amputation neuroma can cause stricture.